1. Field of the Invention
The present invention relates to a novel controlled release carrier system for targeted delivery of fragrances, as well as active ingredients, onto fabric, hair, skin, and other biological surfaces that is activated by changes in pH or salt concentration in the system proximate environment, and which provides prolong release of fragrances and other active ingredients over an extended period of time, or yields a high impact fragrance “burst” upon treating the target surface with heat, such as blow drying the hair or ironing the fabric.
2. Description of the Related Art
The household and cosmetic industry has searched for many years for ways to enhance the performance of consumer and diversified products and make them more aesthetically pleasing for the consumers. Consumer acceptance of consumer and diversified products is determined not only by the performance achieved with these products but the aesthetics associated therewith. Fragrance is an important aspect of the successful consumer and diversified products. Fragrances are being utilized, in addition to imparting an aesthetically pleasing odor, to convey to the consumer the product performance and effectiveness (i.e., the hair or the fabric is clean, freshly washed, etc.).
Fragrances are typically added to consumer and diversified products to convey to the consumer the product performance, i.e., provide a fresh, clean impression for these products as well as to surface treat these products. While the fragrance does not add to the performance of consumer and diversified products, it does make these products more aesthetically pleasing and the consumer has come to expect such products to have a pleasing odor. The fragrance plays a major, and often determining, role for the consumer in selecting and purchasing consumer and diversified products. Consumers are becoming increasingly educated and expect a high level of sophistication in their products. Many consumers would prefer for the fragrance, present in these products, to be deposited on the target surface (fabric, skin, hair) and remain there for an extended period of time to convey a lasting impression of freshness. Consumers are also interested in consumer and diversified products that deposit high level of fragrance onto the treated surfaces and release the fragrance upon heat treatment (ironing, blow drying the hair, etc.). Fragrance creation for consumer and diversified products is restricted not only by considerations such as availability and cost, but also by compatibility of the fragrance ingredients with other components in the product composition and the ability of the fragrance ingredients to deposit onto the target surface and survive the wash and rise process. Furthermore, a large amount of fragrance is being lost. Practice has shown that when currently available fabric care products are used, a large fraction of the fragrance is lost during the rinse process due to the solubility of certain fragrance ingredients in aqueous washing compositions, and the fraction of the fragrance which was deposited, quickly evaporates, due to the volatility of fragrance ingredients.
Typical fabric care products such as laundry detergent compositions and fabric softener compositions contain 0.5% to 1% by weight fragrance in their formulations. U.S. Pat. No. 6,051,540, issued to the inventor of this disclosure, discloses that in the course of the washing process wherein clothes are washed with the standard powdered laundry detergent, or fabric softener rinse, a very small fraction of the fragrance that is contained in these fabric care products is actually transferred to the clothes. Tests are described showing that the amount of fragrance that is left as a residue on the clothes can be as low as 1% of the original small amount of fragrance that is contained in these products formulation itself.
Attempts have been made to increase fragrance deposition onto fabric, hair, and skin and to hinder or delay the release of the fragrance so that the treated surface remains aesthetically pleasing for a prolonged length of time. Publications in the prior art indicate attempts to fulfill the foregoing needs.
The pH conditions as well as salt concentration in the various laundry cycles are markedly different, for example, the pH of the wash solution is 9–12 whereas the pH of the rinse water is neutral (pH 7). Differences in pH or salt concentration can also be found in the process of washing the hair with a shampoos or in the process of washing the skin with soaps or shower gels. These differences in pH and salt concentration can be utilized to protect fragrances and other active ingredients, during the wash cycle and deliver them during the rinse cycle under conditions that are more favorable for the deposition of fragrances and other active ingredients.
The prior art of which applicant is aware does not set forth a targeted controlled delivery system that is activated by pH or salt concentration in the system environment that can be incorporated in consumer and diversified products (i.e., fabric care, hair care, and skin care products) to enhance fragrance deposition and other active ingredients onto target surfaces such as, fabric, hair, skin, and other biological surfaces.
It is desirable to provide a method using an efficient and economical process for site-specific targeted delivery of a broad range of fragrances, and fragrance ingredients and other active ingredients onto fabric, hair, skin, and other biological surfaces that is triggered by pH or salt concentration, and prolong the release of fragrances and other active ingredients onto the target site.